Catchy title, huh? Yes, well. Anyhow, for the PMD 3.3 release we upgraded Jaxen from an ancient 1.0-FCS version to a much newer 1.1-beta7 release - thanks to Elliotte Rusty Harold for the suggestion. This upgrade yielded some nice results:

• smaller number of jar files since saxpath merged into jaxen
• 1.1b7 found a couple of rules that had XPath expressions with missing brackets and parentheses
• best of all, the performance improvement is great. A run of the PMD "basic" ruleset, which is almost all XPath rules, dropped from 21 seconds to 17 seconds - a 20% speedup!

I gave props to the Jaxen developers here, although I stupidly posted the message to that list on an old thread rather than starting a new thread. I've only been sending emails to lists for about 7 years, though, so such a new bee mistake is OK, right?

Anyhow, if you're using an old version of Jaxen and you want a performance boost, upgrade to the latest release and enjoy...